Arachis ipaensis, left, and Arachis duranensis, right, are the two species of wild peanut that crossed to provide the genetic blueprint for today’s modern peanut varieties. (Credit: Merritt Melancon/University of Georgia)

Arachis ipaensis, one of the wild peanut varieties that helped to create the modern peanut, was found in the foothills of the Andes in Bolivia and Argentina in the 1970s. (Credit: Merritt Melancon/University of Georgia)

Athens, Ga. – Researchers at the University of Georgia, working with the International Peanut Genome Initiative, have discovered that a wild plant from Bolivia is a “living relic” of the prehistoric origins of the cultivated peanut species.

The peanut that is grown by farmers today is the result of hybridization between two wild species. The hybrid was cultivated by ancient inhabitants of South America and, by selection, was transformed into today’s crop plant.

Comparisons of the DNA sequences of one of the wild species and the cultivated peanut showed that they are almost exactly same; in fact, they are 99.96 percent identical. It’s an unprecedented similarity.

“It’s almost as if we had traveled back in time and sampled the same plant that gave rise to cultivated peanuts from the gardens of these ancient people,” said David Bertioli, an International Peanut Genome Initiative, or IPGI, plant geneticist of the Universidade de Brasília, who is working at UGA.

This discovery forms part of a study that appears in this month’s Nature Genetics journal, published by the UGA-led IPGI. Scott Jackson, director of the UGA Center for Applied Genetic Technologies in the College of Agricultural and Environmental Sciences, serves as chair of the IPGI. Bertioli is lead author on the paper.

Because its ancestors were two different species, today’s peanut carries two separate genomes, designated “A” and “B” subgenomes. Their high similarity means they are very difficult to map out separately when sequencing the cultivated peanut genome. So, as a first step, researchers built their models using the two wild, ancestral peanut species collected by botanists in the wooded foothills of the Andes in Bolivia and Argentina decades ago.

The genome of one of them, Arachis duranensis, is about as similar to the A subgenome as could be expected. However, what really caught their attention was that the genome of the other species, A. ipaensis, was found to be virtually identical to the B subgenome.

Soon after its collection in 1971, the botanists who collected A. ipaensis realized that it was peculiar. The population of A. ipaensis was very small and isolated, and its closest relatives grew hundreds of miles to the north. They questioned how it arrived in the location where they found it growing.

Prompted by the extraordinary DNA identity, the scientists used information from decades-old botanical collections, knowledge of the seasonal movements of ancient hunter-gatherer-farmers and molecular DNA clock calculations to work out that the plants’ seeds had almost certainly been transported by humans about 10,000 years ago.

“Everything fit,” Bertioli said. “It’s the only place where A and B genome species have ever been found growing close together. The region is right next to the region where, even today, the most primitive types of cultivated peanut are grown, and the date is right in the time frame that plant domestication was happening in South America.”

The movement of the B genome species into the range of the A genome species meant that the hybridization could happen, probably courtesy of a native bee, and the cultivated peanut species was formed. The rest is history, Bertioli said.

The new peanut genome sequences were released in 2014 to researchers and plant breeders around the globe. Their use is advancing the breeding of more productive and more resilient peanut varieties. The paper in Nature Genetics represents the first official publication of the IPGI.

The effort to sequence the peanut genome took several years. While peanuts have been successfully bred for intensive cultivation, relatively little was known about the legume’s genetic structure because of its complexity, according to Peggy Ozias-Akins, a senior author on the paper and director of the UGA Institute of Plant Breeding, Genetics and Genomics. The sequences provide researchers access to 96 percent of all peanut genes and provide the DNA map needed to more quickly identify and genetically tag genes that confer desirable traits, such as drought- and disease-resistance.

A consortium of peanut growers, peanut shellers, brokers and food manufacturing groups provided $6 million in funding for the genome sequencing effort through The Peanut Foundation.

Victor Nwosu, program manager for Mars Chocolate and chairman of the board of directors of The Peanut Foundation, is enthusiastic about the advances these discoveries will facilitate.

“The peanut genome project will lead to reduction in production costs through development of disease-resistant varieties and improved yield for farmers, speed of selection and release of new varieties for breeders and potential for improvement of nutritional value of peanuts for consumers,” Nwosu said. “We are beginning to see these benefits already.”

The International Peanut Genome Initiative brings together scientists from the U.S., China, Brazil, India, Australia, Japan and Israel to delineate peanut genome sequences, characterize the genetic and phenotypic variation in cultivated and wild peanuts and develop genomic tools for peanut breeding. The initial sequencing was carried out in Shenzhen, China, by the BGI, known previously as the Beijing Genomics Institute.

Assembly was done at the BGI, the U.S. Department of Agriculture Agricultural Research Service in Ames, Iowa, and the University of California, Davis. The project was funded by the peanut industry through The Peanut Foundation and by Mars Inc. and three Chinese academies: the Henan Academy of Agricultural Sciences, Chinese Academy of Agricultural Sciences and Shandong Academy of Agricultural Sciences.

CARACOLLO, Bolivia – It’s as inhospitable as climates come for crop cultivation, the dry and rocky soils of Bolivia’s semiarid altiplain. Miguel Choque can see his breath as surveys his fields of quinoa, the Andean “supergrain.”

In late March or April, the flowering plants will paint the rugged landscape yellow, green and red. Their diminutive seed, which powered Inca armies only to be elbowed aside by the wheat preferred by colonizing Spaniards, is unmatched in nutritional value.

Quinoa’s rising popularity among First World foodies — the wholesale price has jumped sevenfold since 2000 as global demand climbed — has been a boon to the poor farmers here in the semiarid highlands where most of it grows.

President Evo Morales’ government has deemed quinoa a “strategic” foodstuff, essential to this poverty-afflicted nation’s food security. It is promoting the grain and has included quinoa in a subsidized food parcel for pregnant women.

Yet the higher prices quinoa is fetching have had an unanticipated impact where the grain is grown. Some local children are showing signs of malnutrition because their parents have substituted rice and noodles for quinoa in the family diet, said Walter Severo, president of a quinoa producer’s group in southwest Bolivia.

“Only 10 percent of it stays in Bolivia. The other 90 percent gets exported,” says Rural Development Minister Nemecia Achacollo.

Quinoa (pronounced KEEN-wah) provides 10 essential amino acids, is loaded with minerals and has a high protein content — between 14 and 18 percent. The FAO (U.N. Food and Agriculture Organization) says it is so nutritious it can be substituted for mother’s milk.

“This food is about the most perfect you can find for human diets,” said Duane Johnson, a 61-year-old former Colorado State agronomist who helped introduce it to the United States three decades ago.

Quinoa isn’t a cereal. It’s a seed that is eaten like a grain, but is gluten-free and more easily digestible than corn, wheat, rye, millet and sorghum. And it can be substituted for rice in just about anything — from soup to salad to pudding to bread.

“I’ve got high-performance athletes that swear by it,” said David Schnorr, president of Quinoa Corp., the largest U.S. importer. It’s also being embraced by the increasing number of Americans with food allergies or celiac disease, an immunological rejection of gluten, a wheat protein. NASA researchers consider it ideal for inclusion in possible future long-term space missions when crops would need to be grown on spacecraft.

Quinoa has been cultivated in the Andean highlands since 3,000 B.C., and grows natively from Chile north to Colombia, mostly in Peru and Bolivia. The varieties of this region of southwestern Bolivia — at 3,700 meters (over 12,000 feet) — are resistant to the freezes and droughts that periodically afflict it.

The crop — “chisiya mama” or mother grain in the native Quechua language — also grows in the San Luis Valley of Colorado at about 8,000 feet (2,400 meters) as well as in a growing number of countries including China and Mongolia, said Johnson.

“It’s very specific in the environments where it will grow,” he said. “It requires very cool days and even cooler evenings.”

He says Peru and Bolivia account for as much as 97 percent of global production.

And demand is booming.

“We’ve easily doubled our business in the last couple of years during the worst economic recession we’ve had in a long time,” said Schnoor.

Schnoor said prices soared threefold in early 2008. A decade ago, a 12-ounce box of his quinoa, marketed under the Ancient Harvest brand, retailed for 99 cents in the United States. Now it costs about $4.50. It’s also available in bulk at natural food markets — and even Costco warehouse stores now carry it.

The indigenous Bolivians who cultivate quinoa are among Bolivia’s poorest and many lived until the late 20th century by barter. It was the discovery of quinoa by the health conscious in wealthier countries that introduced these people to the life of the market, says Brigido Martinez, president of the National Association of Quinoa producers, ANAPQUI.

Martinez traces the boom in quinoa’s popularity to a visit by the king and queen of Spain in 1987, when the royals sampled it, and the news media and the world took note. Food exporters in the coastal Peruvian capital of Lima, where it had been considered “poor people’s food” by the European-descended elite, took note and began buying it up.

It’s not by chance that most of the world’s quinoa comes from Bolivia.

In the 1990s, Johnson and fellow Colorado State University crop scientist Sarah Ward patented a high-yielding hybrid with the intention of spurring large-scale cultivation in the U.S. But they were challenged by ANAPQUI in an international court and abandoned the effort.

There are those in Bolivia who believe this scrappy grain could lift its altiplain out of poverty just as soy has become the economic motor of the country’s wealthier eastern lowlands. After all, quinoa fetches up to five times the price of soy beans in the U.S. and European markets.

Martinez doesn’t believe that can or will happen. For one, quinoa growers farm on a smaller scale (the country’s soy growers are mostly agribusinessmen with huge plantations).

But for a government that proudly declares itself “decolonizing” Bolivia in favor of its long downtrodden indigenous majority, the promotion of quinoa is a linchpin of an agricultural policy that favors the small holder over agribusiness.

Officials are working on details of a plan to boost quinoa production, including credits for farmers that never before had access to financing. Many producers are suspicious, however, that the government could turn into a competitor.

“Its support is fine, but we’d like it to help with irrigation and research to improve the quality of the seed and soil performance,” said Martinez.

Meanwhile, some quinoa farmers have put their increased income to work raising more llamas and alpacas, whose waste is used as fertilizer and which also produce wool. And while most harvesting is still done manually, some have abandoned the ox-pulled plow for tractors.

Some farmers believe current cultivation methods inadequate.

“The soils are tired and need nutrition. Production is dropping,” said Francisco Quisbert, an indigenous leader in the region where Quinoa Real is grown.

But other quinoa boosters caution that traditional, organic farming methods must be maintained to preserve the purity of the crop.

Consumers in the developed world don’t want quinoa grown with chemical fertilizers or pest controllers, said Schnorr.

However it plays out, Martinez, the producer’s association president, is not complaining.

“Quinoa isn’t lifting us out of poverty,” he says. “But we are living better.”